X-Wind in a D-120 ( ex OO-FDP ) now G-BYBE I believe
Correct, but the Chipmunk does not have a FLAT fuselage. It is round, and has less problems with X-Wind.
A free castering tailwheel can not help you maintain direction as well as a steerable tailwheel.
1. Torque, indeed th C-90 has quite some torque and the engine in a D-120 has no offset to correct it.
2. The moment you lift the tail. That very moment the aircraft WILL veer to the left. (Gyroscopic precision), so actually you need MORE right rudder input, the moment you push the nose over.
3. Best practise when in doubt? Keep the tailwheel on the ground untill positive rudder control can be achieved, and be prepared to give more right rudder the moment you lift the tailwheel OFF the ground.
4. And indeed, use ailerons.
Yes, i was talking about the vertical ax at the tailwheel pivot point.